﻿#region File Description
//-----------------------------------------------------------------------------
// Projectile.cs
//
// Attack of the Crazy Pixels
// Copyright (c) 2009 VosSoft
//-----------------------------------------------------------------------------
#endregion
#region License
//-----------------------------------------------------------------------------
// The MIT License (MIT)
//
// Copyright (c) 2009 VosSoft
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//-----------------------------------------------------------------------------
#endregion

#region Using Statements
using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Audio;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.GamerServices;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;
using Microsoft.Xna.Framework.Media;
using Microsoft.Xna.Framework.Net;
using Microsoft.Xna.Framework.Storage;
#endregion

namespace Attack_of_the_Crazy_Pixels
{
    /// <summary>
    /// Defines a Projectile that can be fired from a WeaponTower.
    /// </summary>
    public sealed class Projectile : Sprite
    {
        float speed;

        /// <summary>
        /// Creates a new Projectile.
        /// </summary>
        /// <param name="startPosition">The startPosition where the Projectile is being fired.</param>
        public Projectile(ProjectileInfo info, Vector2 startPosition)
            : base(info.Texture, startPosition, info.Color)
        {
            speed = info.Speed;

            if (info.Size.X != Texture.Width || info.Size.Y != Texture.Height)
            {
                if (Texture == SpriteManager.BlankTexture)
                {
                    Scale = info.Size;
                }
                else
                {
                    Scale = new Vector2(info.Size.X / Texture.Width, info.Size.Y / Texture.Height);
                }
            }
        }

        /// <summary>
        /// Updates the Projectiles position and rotation acording the target.
        /// The Projectile is actually following the Enemy, even if it's changing direction.
        /// </summary>
        /// <param name="elapsedTime">Time since the last frame (in seconds).</param>
        /// <param name="projectileToTarget">The vector from the projectile to the target.</param>
        public void Update(float elapsedTime, Vector2 projectileToTarget)
        {
            projectileToTarget.Normalize();
            Position += projectileToTarget * speed * elapsedTime;
            Rotation = Calc.VectorToRadians(projectileToTarget);
        }
    }
}
